This is real (pardon the pun) interesting. I thought: they have missed the obvious, use int. Wrong:
my $x;

for ($x=1; int($x) <= 2; $x += 0.1) {
  print "$x\n";
}

print "Stop: x=$x\n";
print "No, x is not 2.\n" if $x != 2;

[download]
Gives:
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
Stop: x=3
No, x is not 2.

[download]
So then I RTFM on int.
Changing the comparisons to text (the comparison operators stringify both sides) the result is correct, but of course this is not a solution for numbers greater than 9.

In reply to Re: When is a 2 not a 2? by cdarke
in thread When is a 2 not a 2? by RockM66

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